package com.mrd.shiptask_shipowner.activity;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.io.Writer;
import java.lang.Thread.UncaughtExceptionHandler;
import java.lang.reflect.Field;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.os.Build;
import android.os.Environment;
import android.os.Looper;
import android.util.Log;
import android.widget.Toast;

public class CrashHandler implements UncaughtExceptionHandler {
	public static final String	            TAG	      = "CrashHandler";

	// 系统默认的UncaughtException处理类
	private Thread.UncaughtExceptionHandler	mDefaultHandler;
	// CrashHandler实例
	private static CrashHandler	            instance;
	// 程序的Context对象
	private Context	                        mContext;
	// 用来存储设备信息和异常信息
	private final Map<String, String>	    infos	  = new HashMap<String, String>();

	// 用于格式化日期,作为日志文件名的一部分
	@SuppressLint("SimpleDateFormat")
	private final DateFormat	            formatter	= new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");

	/** 保证只有一个CrashHandler实例 */
	private CrashHandler() {}

	/** 获取CrashHandler实例 ,单例模式 */
	public static CrashHandler getInstance() {
		if(instance == null)
			instance = new CrashHandler();
		return instance;
	}

	/**
	 * 初始化
	 */
	public void init(Context context) {
		mContext = context;
		// 获取系统默认的UncaughtException处理器
		mDefaultHandler = Thread.getDefaultUncaughtExceptionHandler();
		// 设置该CrashHandler为程序的默认处理器
		Thread.setDefaultUncaughtExceptionHandler(this);
	}

	/**
	 * 当UncaughtException发生时会转入该函数来处理
	 */
	@Override
	public void uncaughtException(Thread thread,Throwable ex) {
		if(!handleException(ex) && mDefaultHandler != null) {
			// 如果用户没有处理则让系统默认的异常处理器来处理
			mDefaultHandler.uncaughtException(thread, ex);
		} else {
			try {
				// 使用Toast来显示异常信息
				new Thread() {
					@Override
					public void run() {
						// 收集设备参数信息
						collectDeviceInfo(mContext);
						Looper.prepare();
						Toast.makeText(mContext, "很抱歉,程序出现异常,即将退出.", Toast.LENGTH_SHORT).show();
						Looper.loop();

					}
				}.start();
				Thread.sleep(1000);
			} catch (InterruptedException e) {
				Log.e(TAG, "error : ", e);
			}
			// 退出程序
			android.os.Process.killProcess(android.os.Process.myPid());
			System.exit(0);
		}
	}

	/**
	 * 自定义错误处理,收集错误信息 发送错误报告等操作均在此完成.
	 * @param ex
	 * @return true:如果处理了该异常信息;否则返回false.
	 */
	private boolean handleException(Throwable ex) {
		if(ex == null) {
			return false;
		}

		// 保存日志文件
		saveCatchInfo2File(ex);
		return true;
	}

	/**
	 * 收集设备参数信息
	 * @param ctx
	 */
	public void collectDeviceInfo(Context ctx) {
		try {
			PackageManager pm = ctx.getPackageManager();
			PackageInfo pi = pm.getPackageInfo(ctx.getPackageName(), PackageManager.GET_ACTIVITIES);
			if(pi != null) {
				String versionName = pi.versionName == null ? "null" : pi.versionName;
				String versionCode = pi.versionCode + "";
				infos.put("versionName", versionName);
				infos.put("versionCode", versionCode);
			}
		} catch (NameNotFoundException e) {
			Log.e(TAG, "an error occured when collect package info", e);
		}
		Field[] fields = Build.class.getDeclaredFields();
		for(Field field : fields) {
			try {
				field.setAccessible(true);
				infos.put(field.getName(), field.get(null).toString());
				Log.d(TAG, field.getName() + " : " + field.get(null));
			} catch (Exception e) {
				Log.e(TAG, "an error occured when collect crash info", e);
			}
		}
	}

	/**
	 * 保存错误信息到文件中
	 * @param ex
	 * @return 返回文件名称,便于将文件传送到服务器
	 */
	private String saveCatchInfo2File(Throwable ex) {

		StringBuffer sb = new StringBuffer();
		for(Map.Entry<String, String> entry : infos.entrySet()) {
			String key = entry.getKey();
			String value = entry.getValue();
			sb.append(key + "=" + value + "\n");
		}

		Writer writer = new StringWriter();
		PrintWriter printWriter = new PrintWriter(writer);
		ex.printStackTrace(printWriter);
		Throwable cause = ex.getCause();
		while(cause != null) {
			cause.printStackTrace(printWriter);
			cause = cause.getCause();
		}
		printWriter.close();
		String result = writer.toString();
		sb.append(result);
		try {
			long timestamp = System.currentTimeMillis();
			String time = formatter.format(new Date());
			String fileName = "crash-" + time + "-" + timestamp + ".log";
			if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
				String path = Environment.getExternalStorageDirectory().getPath() + "/crash/";
				File dir = new File(path);
				if(!dir.exists()) {
					dir.mkdirs();
				}
				FileOutputStream fos = new FileOutputStream(path + fileName);
				fos.write(sb.toString().getBytes());
				// 发送给开发人员
				sendCrashLog2PM(path + fileName);
				fos.close();
			}
			return fileName;
		} catch (Exception e) {
			Log.e(TAG, "an error occured while writing file...", e);
		}
		return null;
	}

	/**
	 * 将捕获的导致崩溃的错误信息发送给开发人员
	 * 目前只将log日志保存在sdcard 和输出到LogCat中，并未发送给后台。
	 */
	private void sendCrashLog2PM(String fileName) {
		if(!new File(fileName).exists()) {
			Toast.makeText(mContext, "日志文件不存在！", Toast.LENGTH_SHORT).show();
			return;
		}
		FileInputStream fis = null;
		BufferedReader reader = null;
		String s = null;
		try {
			fis = new FileInputStream(fileName);
			reader = new BufferedReader(new InputStreamReader(fis, "GBK"));
			while(true) {
				s = reader.readLine();
				if(s == null)
					break;
				// 由于目前尚未确定以何种方式发送，所以先打出log日志。
				Log.i("info", s.toString());
			}
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {   // 关闭流
			try {
				reader.close();
				fis.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
}